BO... Rev. T'. Hincks on the 
Lepralia claviculata, n. sp. (PI. III. fig. 2.) 
Zoecia ovate or lozenge-shaped (sometimes irregular in 
shape and size), regularly quincuncial, depressed; surface 
glossy, thickly covered with minute circular punctures, which 
give it a pretty speckled appearance ; orifice arched and ex- 
panded above, more or less narrowed downwards, contracted 
by a small acute projection on each side just above the lower 
margin, which is distinctly curved; peristome not raised. 
Avicularia keyhole-shaped, placed on a distinct area, very 
much smaller than that of the cell, sometimes immediately 
above a zoceclum, more commonly in the angle between two 
zocecia ; mandible directed upwards. Occium (fig. 2 a) very 
large, higher than broad, depressed towards the opening, and 
often grooved longitudinally above the oral arch, rising above 
into a kind of central knob (but on the whole not much ele- 
vated), white, glossy, thickly punctured. 
Zoarium forming large, spreading, whitish crusts. 
Houston-Stewart Channel; Cumshewa, 20 fms. 
Cases occur in which the avicularium is situated on an area 
almost as large as that of the cells, just below the upper 
extremity, occupying, in fact, the position of the oral aperture. 
Occasionally two of these appendages occur together, either 
placed one above the other or side by side. 
PoRELLA, Gray. 
Porella concinna, Busk. 
Cumshewa, on shell. 
[ Britain, Adriatic, Finmark, Norway, Spitzbergen, Franz- 
Josef Land (fdley), Greenland, Gulf of St. Lawrence, 
Bass’s Straits. | 
A beautiful variety occurs in which the whole surface of 
the cell, except the umbo below the orifice, is covered with 
rather large punctures; the orifice is ample, and its characteristic 
features are very distinctly marked. The zoarium is white, 
and delicate in texture. 
Porella marsupium, MacGillivray, form porifera. 
(PI. IV. fig. 4.) 
This species, which is a common Australian form, occurs 
abundantly amongst the dredgings. The specimens from the 
Queen Charlotte Islands differ from those which I have exa- 
mined from Bass’s Straits in one or two points, but they are 
quite unimportant. On the front of the suboral swellin 
which supports the avicularium, are two (or occasionally three) 
